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Richard M. Silver, James E. Potzick, Fredric Scire, Robert D. Larrabee
The reduced critical dimensions of semiconductor devices place more stringent requirements on the precision and accuracy of overlay metrology tools used to monitor stepper feature placement. The use of mix and match stepper techniques and step and scan
Two Monte Carlo computer codes have been written to simulate the transmitted-, backscattered-, and secondary-electron signals from targets in a scanning electron microscope. The first discussed, MONSEL-II, is applied to semi-infinite lines produced
Photomask linewidth standards serve as primary standards for the calibration of photomask metrology tools and are available from the national standards organizations of several countries. These standards are often in the form of chrome-on-quartz photomasks
Ronald G. Dixson, N. Sullivan, J Schneir, T Mcwaid, V W. Tsai, J Prochazka, M. Young
Despite the widespread acceptance of SEM metrology in semiconductor manufacturing, there is no SEM CD standard currently available. Producing such a standard is challenging because SEM CD measurements are not only a function of the linewidth, but also
Nien F. Zhang, Michael T. Postek, Robert D. Larrabee, L Carroll, William J. Keery
Traditionally, the measurement of pitch in metrology instruments is thought to be a benign self-compensating function. However, as the measurement uncertainty of metrology instruments is pushed to the nanometer level, evaluation of the performance of the
Fully automated or semi-automated scanning electron microscopes (SEM) are now commonly used in semiconductor production and other forms of manufacturing. The industry requires that an automated instrument must be routinely capable of 5 nm resolution (or
Ronald G. Dixson, J Schneir, T Mcwaid, N. Sullivan, V W. Tsai, S Zaidi, S Brueck
As the critical dimensions of integrated circuit features decrease toward 0.18 um, feature width measurements with nanometer level accuracy will become increasingly important to the semiconductor processing industry. Atomic force microscopy (AFM) offers
A specific example of a technique we developed to enhance the information obtained from SEM images is the extraction of an approximate profile corresponding to an electron beam with zero beam diameter from one with a finite beam diameter. Results were
In scanned probe microscopy the image is a combination of information from the sample and the tip. In order to reconstruct the true surface geometry, it is necessary to know the actual tip shape. It has been proposed that this shape may be reconstructed
Wave-front or surface errors may be divided into rotationally symmetric and nonrotationally symmetric terms. It is shown that if either the test part or the reference surface in an interferometric test is rotated to N equally spaced positions about the
E W. Paul, Christopher J. Evans, A Mangamelli, Michael L. McGlauflin, Robert S. Polvani
A hypothesis is proposed that ascribes chemical wear of diamond tools to the presence of unpaired d electrons in the sample being machined. This hypothesis is used to explain a range of results for metals, alloys, and other materials including electroless
The development and application of digital imaging technology has been one of the major advancements in scanning electron microscopy (SEM) during the past several years. This digital revolution has been brought about by significant progress in
Zeina J. Kubarych, S Milosevic, A Allegrini, J Huennekens, R K. Namiotka
We report experimental rate coefficients for the energy-pooling collisions Cs(6P/sub 1/2/)+Cs(6P/sub 1/2/) to Cs(6S/sub 1/2/)+Cs(nl/sub J''/) and Cs(6P/sub 3/2/)+Cs(6P/sub 3/2/) to Cs(6S/sub 1/2/)+Cs(nl/sub J''/) where nl/sub J''/=7P/sub 1/2/, 7P/sub 3/2/
Lowell P. Howard, Fredric Scire, Jack A. Stone Jr.
A description of a Fabry-Perot interferometer for measuring small displacements is given. The instruments consists of a fiber-optic-coupled actuator and mirror guiding mechanisms, a tunable diode laser for tracking the changes in cavity length and a
V W. Tsai, Theodore V. Vorburger, P Sullivan, Ronald G. Dixson, Richard M. Silver, Edwin R. Williams, J Schneir
The decreasing feature dimensions required in the semiconductor manufacturing industry are placing ever increasing demands upon metrology instruments. Atomic force microscopes (AFMs), which can have 1 nm lateral resolution and sub-angstrom vertical
An equation for an unknown surface field that represents scattering by a rough patch on a flat dielectric surface is presented. The geometrical considerations for this particular problem are discussed, especially in relation to a surface divergence factor.
J Mcclelland, Robert Celotta, Zeina J. Kubarych, R Gupta
Laser focusing of atoms has emerged as a viable form of nanofabrication. Structures are formed by focusing chromium atoms as they deposit onto a surface. The focusing occurs in a standing-wave laser field in one or two dimensions, resulting in arrays
During the 1996 CMSC conference, undoubtedly one of the hottest topics was how to achieve traceability for the laser tracker. This paper reviews the concepts of traceability and measurement uncertainty from NIST''s perspective, and explain how these topics
The National Institute of Standards and Technology is developing a simple one-dimension certified pitch standard (or scale) covering the range 1 um to 10 mm, intended for the calibration of microscope magnification and dimensional metrology instrument
Jack A. Stone Jr., Lowell P. Howard, Alois Stejskal, M Stephens, C Oates, L Hollberg
Diode lasers have several unique capabilities for length-measurement applications, arising from properties of the diodes that are much different from those of the venerable helium-neon laser presently used for most interferometric measurements. For example
Richard M. Silver, Amy Singer, L Carroll, S Berg-cross, James E. Potzick
Many of the significant challenges in making accurate overlay registration measurements are discussed. An understanding of the causes of the errors affecting these measurements is a prerequisite to improving accuracy and also for the design of standard
T Mcwaid, J Schneir, John S. Villarrubia, Ronald G. Dixson, V W. Tsai
Accurate metrology using atomic force microscopy (AFM) requires accurate control of the tip position, an estimate of the tip geometry, and an understanding of the tip-surface interaction forces. We describe recent progress at NIST towards accurate AFM
The standard interpretation of quantum mechanics is revised to conform to the relativistic theory based on the many-amplitudes formalism for the N-particle system. The wave function acquires a significance closer to that of the electromagnetic field, with